This application claims priority under 35 U.S.C. xc2xa7xc2xa7119 and/or 365 to SE 9701845-1 filed in Sweden on May 16, 1997; the entire content of which is hereby incorporated by reference.
The present invention relates to a telecommunications system especially one that includes a mobile communications system and a mobile locating means with which the geographical location of a terminal in the mobile communications system can be determined.
The manner in which the geographical location of a mobile station in a mobile communications system can be determined is described in a large number of patent specifications.
Some patent specifications, for instance SE 9500569-0, Europolitan, describes a procedure with which the location of a mobile station is determined by the American GPS system. This requires the mobile station to be also equipped with a GPS terminal. A GPS terminal can determine its geographical location, by receiving signals from at least three satellites. An inquiry from a third party concerning the location of the mobile station can be sent over the mobile communications system and handled by the mobile station without involving its user. The location of the mobile station is then sent back over the network to the person requesting the information.
In the majority of these solutions, the measurements necessary for establishing the location of the mobile station are carried out by the mobile communications system instead. For instance, Patent Specification SE 9603561-3, Bodinl, describes how the wave propagation time of a signal from the mobile station is measured in a base station. The wave propagation time is corresponded by a distance. The measuring process is repeated at two more base stations. The location of the mobile station can then be established on the basis of the measuring results and on the knowledge of the geographical locations of the base stations. According to this prior patent specification, the calculation is made in a mobile locating node belonging to the mobile communications system.
Alternatively, the wave propagation time of a signal sent from a base station may be measured in the mobile station. This method is described in Patent Specification U.S. Pat. No. 5,293,645, Sood, among others. After having measured the wave propagation from at least three base stations, the mobile station reports the result to the land based part of the mobile communications network.
It is also mentioned in SE 9500569-0 that the geographical location of a mobile station can be determined through the identity of the cell within which the mobile station is located. It is the mobile communications system that is able to obtain the cell identity information. This method can only provide a rough indication of the location of the mobile station, since the indicated cell may well have a radius in the order of tens of kilometres.
Patent Specification SE 9700522-7, Bodin2, describes how a mobile locating command can be sent from a mobile locating node outside the mobile communications system to the mobile switching center that manages the mobile station. The switching center is assumed to control the base station system to carry out measurements that will determine the location of the mobile station with the aid of some earlier known measuring method. The mobile locating node provides a mobile locating service, in which it receives orders from a customer concerning the location of a certain mobile station, orders the switching center to carry out a measuring procedure, receives the measuring result, and calculates the location of the mobile and then presents the result to the customer. A modified short message service (SMS) is used to send the command to the switching center and to send the measuring result from the switching center to the mobile locating node.
None of the aforementioned patent specifications draws attention to the encroachment of the integrity of a user of a mobile station when an outsider is able to establish the geographical location of the user.
The present invention addresses the problem of an outsider being able to establish the geographical location of a mobile station with the aid of a mobile locating service. Determination of the geographical location of a mobile constitutes a problem when it takes place against the wishes of the mobile user.
Another problem addressed by the invention is when the user of the mobile station may wish an outsider to be informed of his location on certain occasions while keeping the possibility of preventing an outsider from being informed of his location on other occasions.
Another problem is one when the user may wish for a person of his choice to be informed of his location while denying this possibility to other persons.
Accordingly, an object of the present invention is to protect the integrity of a mobile user, such as to prevent outsiders from determining the location of the mobile with the aid of a mobile locating service. Another object is to provide a flexible integrity protection service which enables the geographical location of the mobile to be determined when the user so desires or when it is in the user""s interest for the location of the mobile to be determined.
The aforesaid problems are solved in accordance with the present invention, by providing the mobile communications system with an indicator. The indicator is set either to indicate that the user permits the location of the mobile to be determined, i.e. a permission granted state, or to a state in which the user does not permit the location of the mobile to be determined, i.e. permission not granted state. Before determining the location of a mobile, a check is made to ascertain whether or not the indicator is in its permission granted state. If not, the location determining process is discontinued. The user of the mobile is able to set the indicator to the state desired. In one embodiment the subscriber, i.e. the owner of the subscription which may be different than the current user, has the possibility to prevent someone who is using the subscriber""s mobile station MS from changing the indicator.
According to one alternative embodiment, the user of the mobile receives a request for permission to determine the location of his mobile. This embodiment can be suitably used when the user himself has requested from a service provider a service that is dependent on the geographical location of the user. The service provider contacts a mobile locating node and asks to be told of the location of the mobile station. The mobile locating node asks the user for permission to determine the location of the mobile. The user gives his permission directly to the mobile locating node. Alternatively, the user gives his permission to the mobile locating node via the service provider. This is effected by sending to the service provider a code that the user has received together with the permission request, wherewith the service provider sends the code to the mobile locating node. The location of the mobile is determined when the code received agrees with the code sent together with the request.
In addition to checking the permission indicator, a check can also be made to ascertain whether or not the person requesting determination of the location of the mobile is registered and that authorization for this person to establish the location of the sought mobile is also registered, said checks being carried out before determining the location of the mobile. In this case, registration of this information is a condition for allowing the location of the mobile to be determined. This information is stored in a register connected to or integrated with the mobile locating node.
The invention provides the advantage of enabling the user of a mobile station to prevent the geographical location of the mobile being established and divulged. The invention can be applied in a number of different forms that are suited for different situations. For instance, this enables a haulage contractor to establish the locations of its own mobile stations regularly and in a simple manner, while, at the same time, preventing others from establishing the locations of said mobiles. It also enables a private user to prevent the location of his mobile station being determined while, at the same time, enabling the user to establish his own location on certain occasions when needed by the user. The various embodiments of the invention thus enable the integrity of the user to be protected in a flexible manner.
The invention also has the advantage of being adapted for the administrative structure in the mobile communications system. It is essential to adapt to the existing structure, so as not to increase the complexity of the mobile communications system. The introduction of the indicator in the mobile communications system enables the user to set the indicator to the state desired directly and involves a only minor modification of the mobile communications system.